1. Field of the Invention
The present invention relates to a method for manufacturing a battery.
2. Description of the Related Art
Batteries such as a lithium ion secondary battery have been studied for further performance improvements. As a prior art technique related thereto, Japanese Patent Application Publication No. 2011-23186 discloses a separator for an electrochemical element. The separator has an adhesive resin layer which is melted by heating to show an adhesive property. According to the technique disclosed in Japanese Patent Application Publication No. 2011-23186, a positive electrode, a separator, and a negative electrode are stacked in this order and hot-pressed. This integrates at least one of the positive and negative electrodes with the separator via an adhesive resin layer. As a result, even when charging/discharging is repeated, the distance between the positive electrode and the negative electrode is less likely to vary to allow an improvement in charge/discharge cycle characteristic.
However, the technique disclosed in Japanese Patent Application Publication No. 2011-23186 requires the steps of forming the adhesive resin layer on the surface of the separator, specifically the steps of preparing a slurry for forming the adhesive resin layer, applying the slurry, and drying the applied slurry. As a result, a problem arises in that the number of steps increases to significantly reduce productivity. In addition, since the separator disclosed in Japanese Patent Application Publication No. 2011-23186 has the adhesive resin layer, the entire thickness of the separator increases. This may increase resistance and degrade battery performance, e.g., an input/output density.